The present invention relates to herbicidal compounds useful in agriculture and related industries. More specifically, the present invention relates to a new class of compounds effective as selective herbicides, to compositions comprising such compounds, and to methods of controlling weeds with such compounds and compositions thereof.
Triazole derivatives have, for many years, been investigated for a wide range of utilities. For example, Potts, Chemical Reviews, 61, 87-127 (1961) is cited in U.S. Pat. No. 3,308,131 as showing that various 1,2,4-triazole compounds have found commercial application as herbicides, defoliants, photographic reagents, rubber chemicals and in polymers. U.S. Pat. No. 3,308,131 itself discloses 1,2,4-triazole compounds having a di-aliphatically substituted tertiary carbamoyl group attached to a nitrogen atom of the triazole nucleus, and in which the carbon atoms of the triazole nucleus are bonded to hydrogen, halogen, carbon or sulfur atoms. These triazoles are disclosed to be particularly useful as insecticides.
Other 1,2,4-triazoles have been disclosed as having utility as herbicides. For example, U.S. Pat. No. 5,211,739 discloses herbicidal 1-(disubstituted carbamoyl or thiocarbamoyl)-1,2,4-triazol-3-yl sulfonates and thiosulfonates. U.S. Pat. No. 3,952,001 discloses herbicidal 1-carbamoyl-1,2,4-triazoles having haloalkylsulfinyl or haloalkylsulfonyl substituents but teaches that the xe2x80x9chaloalkyl radicalxe2x80x9d is preferably xe2x80x9cattached to a carbon atom other than that which is attached to the . . . sulphur atom of the groupxe2x80x9d defined as the haloalkylsulfinyl or haloalkylsulfonyl moiety. U.S. Pat. No. 4,810,271 discloses herbicidal 1-(disubstituted carbamoyl or thiocarbamoyl)-1,2,4-triazol-3-yl cycloalkyl(lower)alkyl, oxacycloalkyl(lower)alkyl or dioxacycloalkyl(lower)alkyl sulfonates and thiosulfonates. U.S. Pat. No. 4,280,831 discloses one herbicidal compound which is 3-benzylsulfonyl-1-diethylcarbamoyl-1,2,4-triazole.
The present invention provides a compound of formula (I) 
wherein R3 is hydrogen, halogen or a group having a molecular weight of 15 to about 500, having up to 34 carbon atoms and comprising a hydrocarbyl moiety that is unsubstituted or substituted with one or more heteroatom-containing groups wherein heteroatoms are selected from oxygen, sulfur, nitrogen, halogen and silicon, and Z is a carbamoyl or thiocarbamoyl group having directly attached to the nitrogen atom thereof, each by a carbon-nitrogen bond, two substituent groups each independently comprising a C1-14 hydrocarbyl moiety that is unsubstituted or substituted with one or more heteroatom-containing groups wherein heteroatoms are selected from oxygen, nitrogen and halogen, said substituent groups optionally being joined to form, with said nitrogen atom, a ring structure, Z having a molecular weight of 72 to about 500; or an agronomically acceptable acid addition salt or metal complex of a compound of formula (I).
More particularly, the present invention provides a compound of formula (II) 
wherein:
Y is oxygen or sulfur;
R1 and R2 
(a) are each independently a C1-14 hydrocarbyl group, preferably a linear or branched aliphatic or alicyclic group that is saturated or has one or more olefinic and/or acetylenic bonds, and is unsubstituted or substituted with one or more halogen, haloalkyl, hydroxy, alkoxy, carboxy, amido, cyano or amino groups, wherein amido and amino groups are each unsubstituted or further substituted with one or two hydrocarbyl groups; or
(b) together with the carbamoyl nitrogen atom to which they are attached, form a nitrogen-containing five or six membered ring, the ring being optionally interrupted by an ethereal oxygen atom and unsubstituted or substituted with one or more hydroxy, amido, cyano, amino or C1-8 alkyl, alkenyl, alkynyl, cycloalkyl, arylalkyl, alkoxy, aminoalkyl or haloalkyl groups, wherein amido and amino groups are each unsubstituted or further substituted with one or two hydrocarbyl groups;
R1 and R2, together with the carbamoyl or thiocarbamoyl group to which they are attached, having a total molecular weight of 72 to about 500; and
R3 is hydrogen, halogen, or an alkyl, cycloalkyl, alkenyl, cycloalkenyl, cycloalkylalkenyl, aryl, arylalkyl, alkylthio or arylalkylthio group that is unsubstituted or substituted with one or more halo, hydroxy, alkoxy, acetyloxy, benzoyloxy, alkoxycarbonyl, silyl or alkylsilyl groups, wherein aryl rings are unsubstituted or substituted with one to three substituents independently selected from alkyl, alkenyl, alkynyl, cycloalkyl, halo, haloalkyl, alkoxy, haloalkoxy, cyano, nitro, alkoxycarbonyl, alkylthio and haloalkylthio groups; R3 having a molecular weight of 15 to about 500 and having 0-34 carbon atoms;
or an agronomically acceptable acid addition salt or metal complex of a compound of formula (II).
Illustratively, R1 and R2 can be alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, alkylcycloalkyl, alkenylcycloalkyl, alkynylcycloalkyl, cycloalkylalkyl, cycloalkenylalkyl, alkylcycloalkylalkyl, alkenylcycloalkylalkyl, alkynylcycloalkylalkyl, haloalkyl, haloalkenyl, haloalkynyl, halocycloalkyl, alkoxyalkyl, alkoxyalkenyl, alkoxyalkynyl, alkoxycycloalkyl, haloalkoxyalkyl, haloalkoxyalkenyl, haloalkoxyalkynyl, haloalkoxycycloalkyl, halocycloalkylalkyl or alkoxycycloalkylalkyl groups. Alternatively, R1 and R2 can illustratively together form a C4-5 alkylene group that is unsubstituted or substituted with one or two substituents independently selected from halo, hydroxy and alkoxy, alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkylalkyl and cycloalkenylalkyl groups unsubstituted or further substituted with halo, hydroxy, alkoxy, alkyl, alkenyl, alkynyl, cycloalkyl, haloalkyl or haloalkoxy groups.
Illustratively, R3 can be hydrogen, halogen or an alkyl, haloalkyl, cycloalkyl, halocycloalkyl, alkenyl, cycloalkylalkenyl, alkoxyalkenyl, haloalkenyl, cycloalkenyl, halocycloalkenyl, alkylthio, hydroxyalkylthio, alkoxyalkylthio, haloalkylthio, acetyloxyalkylthio, benzoyloxyalkylthio, alkoxycarbonylalkylthio group or an aryl, arylalkyl or arylalkylthio group unsubstituted or substituted as indicated above.
The present invention also provides a composition for use as a herbicide comprising a herbicidally effective amount of a compound of formula (I) or (II) as defined above or an agronomically acceptable acid addition salt or metal complex thereof. Such a composition can be a concentrate, further comprising one or more agronomically acceptable inert formulation ingredients or excipient substances, or it can be ready-to-use, further comprising an agronomically acceptable carrier.
The present invention also provides a method of using a compound of formula (I) or (II) as a herbicidal agent, comprising applying a herbicidally effective amount of such a compound to soil or plants.
Preferred Substituents of Compounds of Formula (II)
In compounds of the invention as defined in formula (II) above, the following are preferred substituents.
Preferably R1 and R2 are independently C1-6 alkyl, C2-4 alkenyl, C2-4 alkynyl, C3-6 cycloalkyl, C5-6 cycloalkenyl, (C1-3)alkyl(C3-6)cycloalkyl, (C2-3)alkenyl(C3-6)cycloalkyl, (C2-3)alkynyl(C3-6)cycloalkyl, halo(C1-6)alkyl, halo(C2-4)alkenyl, halo(C2-4)alkynyl, halo(C3-6)cycloalkyl, (C1-4)alkoxy(C1-6)alkyl, (C1-4)alkoxy(C2-4)alkenyl, (C1-4)alkoxy(C2-4)alkynyl), (C1-4)alkoxy(C3-6)cycloalkyl halo(C1-4)alkoxy(C1-6)alkyl, halo(C1-4)alkoxy(C2-4)alkenyl, halo(C1-4)alkoxy(C2-4)alkynyl, halo(C1-4)alkoxy(C3-6)cycloalkyl, (C3-6)cycloalkyl(C1-4)alkyl, (C5-6)cycloalkenyl(C1-4)alkyl, (C1-4)alkyl(C3-6)cycloalkyl(C1-4)alkyl, (C1-4)alkyl(C5-6)cycloalkenyl(C1-4)alkyl, (C2-4)alkenyl(C3-6)cycloalkyl(C1-4)alkyl, (C2-4)alkynyl(C5-6)cycloalkyl(C1-4)alkyl, halo(C3-6)cycloalkyl(C1-4)alkyl or (C1-4)alkoxy(C3-6)cycloalkyl(C1-4)alkyl; or R1 and R2 together represent an unsubstituted C4-5 alkylene group or a C4-5 alkylene group substituted with one or two substituents each independently selected from the group consisting of C1-4 alkyl, C2-4 alkenyl, C2-4 alkynyl, C3-6 cycloalkyl, C1-4 alkoxy, halo and halo(C1-4)alkoxy, so as to form a nitrogen-containing five or six membered ring together with the carbamoyl nitrogen atom to which they are attached.
Preferably R3 is a hydrogen, halogen, C1-8 alkyl, halo(C1-4)alkyl, C3-6 cycloalkyl, halo(C3-6)cycloalkyl, C2-4 alkenyl, (C3-6)cycloalkyl(C2-4)alkenyl, (C1-4)alkoxy(C2-4)alkenyl, halo(C2-4)alkenyl, C3-6 cycloalkenyl, halo(C3-6)cycloalkenyl, C6-10 aryl or (C6-10)aryl(C1-6)alkyl group, wherein C6-10 aryl or (C6-10)aryl(C1-6)alkyl groups are unsubstituted or substituted on the aryl ring with one to three substituents each independently selected from C1-6 alkyl, C2-4 alkenyl, C2-4 alkynyl, C3-6 cycloalkyl, halo, halo(C1-4)alkyl, C1-4 alkoxy, halo(C1-4)alkoxy, cyano, nitro, (C1-6)alkoxycarbonyl, (C1-4)alkylthio and halo(C1-4)alkylthio groups.
The term xe2x80x9calkylxe2x80x9d in the present specification includes straight and branched chain alkyl groups, for example C1-6 alkyl groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, n-pentyl, isopentyl and n-hexyl groups. The term xe2x80x9calkenylxe2x80x9d includes, for example, C2-4 alkenyl groups such as vinyl, allyl, methallyl and 2-butenyl groups. The term xe2x80x9calkynylxe2x80x9d includes, for example, C2-4 alkynyl groups such as a propargyl group.
The term xe2x80x9chaloxe2x80x9d includes fluoro, chloro, bromo and iodo. The term xe2x80x9calkoxyxe2x80x9d includes, for example, methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy and isobutoxy groups. Illustrative alkoxyalkyl groups include 2-methoxyethyl, 2-ethoxyethyl, 2-propoxyethyl, 2-n-butoxyethyl, 3-methoxypropyl, 3-ethoxypropyl, 2-methoxypropyl and 2-ethoxypropyl groups. Haloalkyl groups include, for example, fluoromethyl, difluoromethyl, chlorodifluoromethyl, bromodifluoromethyl, 2-chloroethyl, 2-bromoethyl, 2-fluoroethyl, 3-chloropropyl, 3-bromopropyl, 4-chlorobutyl, 4-bromobutyl and 5-chloropentyl.
Illustrative C2-4 cycloalkyl groups are cyclopropyl, cyclopentyl and cyclohexyl groups. An illustrative (C3-6)cycloalkyl(C2-4)alkenyl group is a 1-cyclohexyl-1-propen-3-yl group. An illustrative (C2-4)alkoxy(C2-4)alkenyl group is a 4-ethoxy-2-buten-1-yl group. Illustrative C5-6 cycloalkenyl groups are 1-cyclopenten-1-yl and 2-cyclohexen-1-yl groups. An illustrative (C2-3)alkenyl(C3-6)cycloalkyl group is a 1-cyclohexylethen-2-yl group. An illustrative (C2-3)alkynyl(C3-6)cycloalkyl group is a propargylcyclohexyl group.
The term xe2x80x9carylxe2x80x9d as used in the present specification means an aromatic ring structure having, for example, 6-10 carbon atoms, preferably a phenyl or naphthyl group. Typical aryl and substituted aryl groups in compounds encompassed by this invention are phenyl, naphthyl, 2-chlorophenyl, 3-chlorophenyl, 4-chlorophenyl, 4-bromophenyl, 4-fluorophenyl, 2,3-dichlorophenyl, 2,3-difluorophenyl, 2,4-dichlorophenyl, 2-methylphenyl, 3-methylphenyl, 4-methylphenyl, 2,4-dimethylphenyl, 2-chloro-6-methylphenyl, 2-methoxy-3-methylphenyl, 3-methoxy-2-methylphenyl, 3-(trifluoromethyl)phenyl, 4-(trifluoromethyl)phenyl, 2-(difluoromethoxy)phenyl, 4-cyanophenyl, 4-nitrophenyl, 4-methoxyphenyl, 4-(methylthio)phenyl, 4-isopropylphenyl, 2,4,6-trichlorophenyl, 4-iodophenyl, 4-fluoro-2-methylphenyl, 4-chloro-2-methylphenyl, 2-(fluoromethyl)phenyl, 4-(2-chloroethyl)phenyl, 4-t-butylphenyl, 4-t-butoxyphenyl, 2,4-dicyanophenyl, 4-allylphenyl, 4-propargylphenyl, 4-cyclopropylphenyl, 4-cyclohexylphenyl, 4-(chloromethylthio)phenyl, 2-(chloromethoxy)phenyl, 4-(methoxycarbonyl)phenyl and 3-isobutylphenyl.
The term xe2x80x9carylalkylxe2x80x9d as used in the present specification means an alkyl group substituted with an aryl group, for example a (C6-10)aryl(C1-6) alkyl group such as a 1-(naphthyl)methyl, 2-(4-chlorophenyl)ethyl or 6-(2,4-difluorophenyl)hexyl group.
This invention also provides acid addition salts of a compound of formula (II) wherein one or more of the protonatable nitrogen atoms of the compound are protonated and the acid is selected to give an anionic counterion in such a manner that the sum of the valence charges of the protonated compound and the anion equals zero.
This invention further provides metal salt complexes of a compound of formula (II) wherein the salt comprises a cation of a metal selected from Groups IIA, IVA, IB, IIB, VIB, VIIB and VIII of the Periodic Table and an anionic counterion such that the sum of the valence charges of the cation and anion equals zero.
Preparation of Compounds of Formula (II)
A 1-(disubstituted carbamoyl or thiocarbamoyl)-1,2,4-triazole compound of formula (II) can be generally produced by the hereinafter described process.
In such a process, described in Equation 1, a triazole compound having the general formula (III) is reacted with a carbamoyl or thiocarbamoyl halide of the general formula (IV). In formulas (III) and (IV), R1, R2, R3 and Y are as defined for Formula (II) and A is chlorine, bromine or fluorine, preferably chlorine. 
The reaction is suitably effected in a solvent in the presence of an acid acceptor. The equivalent ratio of the triazole compound (III), the carbamoyl or thiocarbamoyl halide (IV) and the acid acceptor is usefully 1:1-1.5:1-10. Examples of suitable solvents are aromatic hydrocarbons (e.g., benzene, toluene, xylene), halogenated hydrocarbons (e.g., chloroform, dichloromethane, chlorobenzene), ethers (e.g., diethyl ether, tetrahydrofuran), ketones (e.g., acetone, 2-butanone),.organic bases (e.g., pyridine, triethylamine, N,N-diethylaniline), acetonitrile, N,N-dimethylformamide, dimethylsulfoxide and water. As the acid acceptor, there can be used inorganic bases (e.g., sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, sodium hydrogen carbonate), organic bases (e.g., pyridine, triethylamine, N,N-diethylaniline), etc. The reaction can normally be carried out at a temperature between the freezing point and the boiling point of the solvent, preferably from 0xc2x0 C. to 150xc2x0 C., within a period of 10 minutes to 48 hours. In an alternative procedure, the triazole compound (III) can be converted to an alkali metal (e.g., sodium, potassium) salt thereof by reacting with an alkali metal hydride, amide or alkoxide in accordance with known methods prior to the reaction with the carbamoyl or thiocarbamoyl halide (IV).
The carbamoyl or thiocarbamoyl halide of formula (IV) can be prepared by reacting a secondary amine of formula HNR1R2, in which R1 and R2 are as defined above for formula (II), with a carbonyl or thiocarbonyl halide CYA2 where A and Y are as defined above for formula (IV), in accordance with known methods.
The triazole compound of formula (III) can be prepared by a process, described in Equation 2, in which a 1-(N,N-diethylcarbamoyl)triazole of formula (V) wherein R3 is as defined above for formula (II) is reacted with a sodium alkoxide (NaOR) in which R is methyl, ethyl, propyl, isopropyl or butyl, the reaction taking place in the corresponding alkanol (ROH) solvent. The sodium salt of the compound of formula (III) thus produced is acidified with dilute mineral acid and extracted with a solvent such as a halogenated hydrocarbon (e.g., chloroform, dichloromethane), ether (e.g., diethyl ether) or ester (e.g., ethyl acetate). 
The reaction can normally be carried out at a temperature between the freezing point and the boiling point of the solvent, preferably from 0xc2x0 C. to 150xc2x0 C., within a period of 10 minutes to 48 hours.
The 1-(N,N-diethylcarbamoyl)triazole of formula (V) can be prepared by a number of routes including the following:
(a) A compound of formula (V) in which R3 is hydrogen, halogen or a haloalkyl, aryl, arylcarbonyl or alkoxycarbonyl group can be prepared by oxidation of a triazole sulfide of formula (VI) 
in accordance with a method described by W. Su, Tetrahedron Letters, 1994, volume 35, pages 4955-4958.
Thus, in a typical reaction, a compound of formula (VI) is stirred with sodium periodate and a catalytic amount of ruthenium trichloride hydrate in a mixture of carbon tetrachloride, acetonitrile and water. The equivalent ratio of triazole sulfide (VI), sodium periodate and ruthenium trichloride hydrate is usefully 1:3-5:0.05. The reaction can normally be carried out at room temperature within a period of 30 minutes to 48 hours, more typically 8-24 hours.
The triazole sulfide of formula (VI) in which R3 is hydrogen can be prepared from the corresponding compound in which R3 is a bromo group by reaction with a reducing agent such as a mixture of ammonium formate and ammonium persulfate in a solvent such as N,N-dimethylformamide.
A triazole sulfide of formula (VI) in which R3 is halo, haloalkyl, aryl, arylcarbonyl or alkoxycarbonyl can be prepared by a process described in Equation 3 in which the 3,3xe2x80x2-(dithiobis)-1,2,4-triazole compound of formula (VII) is reacted with a halide compound of the formula (VIII) in which G is a bromo or iodo group. 
The reaction is suitably effected in a mixture of N,N-dimethylformamide and water in the presence of sodium dithionite and disodium hydrogen phosphate. The equivalent ratio of 3,3xe2x80x2-(dithiobis)-1,2,4-triazole compound (VII), halide compound (VIII), sodium dithionite and disodium hydrogen phosphate is usefully 1:1.5-6:1.5:1.5. The reaction can normally be carried out at a temperature between xe2x88x9278xc2x0 C. and 40xc2x0 C. preferably from 0xc2x0 C. to 25xc2x0 C., within a period of 1 hour to 48 hours.
The 3,3xe2x80x2-(dithiobis)-1,2,4-triazole compound (VII) can be prepared by a process of reacting 3,3xe2x80x2-(dithiobis)-1,2,4-triazole, a compound previously described in French Patent No. 2,592,381, with N,N-diethylcarbamoyl chloride in the presence of an acid acceptor such as pyridine.
(b) Compounds of formula (V) in which R3 is a group xe2x80x94Sxe2x80x94R4 group wherein R4 is an alkyl, arylalkyl, alkoxycarbonylalkyl, hydroxyalkyl or alkoxyalkyl group can be prepared by a process described in Equation 4 in which 3-(bromodifluoromethylsulfonyl)-1-(N,N-diethylcarbamoyl)-1,2,4-triazole (IX), prepared as described above, is reacted with a disulfide compound of formula (X). 
The reaction is suitably effected in a mixture of N,N-dimethylformamide and water in the presence of sodium dithionite and disodium hydrogen phosphate. The equivalent ratio of compound (IX), disulfide compound (X), sodium dithionite and disodium hydrogen phosphate is usefully 1:2:1.5:1.5. The reaction can normally be carried out at a temperature between xe2x88x9278xc2x0 C. and 40xc2x0 C., preferably from 0xc2x0 C. to 25xc2x0 C., within a period of 1 hour to 24 hours.
(c) Compounds of formula (V) in which R3 is a group xe2x80x94Sxe2x80x94R4 group wherein R4 is an alkylcarbonyloxyalkyl or arylcarbonyloxyalkyl group can be prepared from the corresponding compounds in which R4 is a hydroxyalkyl group by reaction with an alkylcarbonyl chloride or an arylcarbonyl chloride in the presence of an acid acceptor such as pyridine or triethylamine.
(d) Compounds of formula (V) in which R3 is a xe2x80x94CH2xe2x80x94C(R5)xe2x95x90CH2 group wherein R5 is hydrogen, halogen or an alkyl or trialkylsilylalkyl group can be prepared by a process described in Equation 5 in which 3-(bromodifluoromethylsulfonyl)-1-(N,N-diethylcarbamoyl)-1,2,4-triazole (IX) is reacted with a 2-(2-alkenylthio)-2-thiazoline compound of formula (XII). 
The reaction is suitably effected in a mixture of N,N-dimethylformamide and water in the presence of sodium dithionite and disodium hydrogen phosphate. The equivalent ratio of compound (IX), 2-(2-alkenylthio)-2-thiazoline compound (XII), sodium dithionite and disodium hydrogen phosphate is usefully 1:2:1.5:1.5. The reaction can normally be carried out at a temperature between xe2x88x9278xc2x0 C. and 40xc2x0 C., preferably from 0xc2x0 C. to 25xc2x0 C., within a period of 1 hour to 24 hours.